Pressurized stopper construction



Dec. 31, 1963 A. v. DE MOLIN ETA]. 3,

PRESSURIZED STOPPER CONSTRUCTION I Filed March 5, 1958 2 Sheets-Sheet l I I34, I 532/ I I 5/ 62 I k 4% i l 60 J54 64 A |H 6: ll 54 fin, 64 .532,

' ja/ -02 -I Dec. 31, 1963 A. v. DE .MOLIN ETA].

PRESSURIZED STOPPER CONSTRUCTION Filed March 5, 1958 2 Sheets-Sheet 2 United States Patent 3,115,868 PRESSURIZED STOPPER CONSTRUCTIGN Arrigo Varettoni de Molin, 88 Lafayette Ave., Park Ridge, N J and Sidney D. Barlow, 232 Magnolia Ave., Mount Vernon, N.Y.

Filed Mar. 5, 1958, Ser. No. 719,397 1 Claim. (Cl. 120-424) T his invention relates generally to ball point marking devices having means for creating above-atmospheric pressures within the ink or marking fluid retaining chamber thereof, and more particularly to an improved pressurized stopper construction employed for closing the open end of a marking tube and for introducing additional pressure within the ink retaining chamber. Reference is made to Patent No. 2,333,451, patented November 2, 1943, by Philip Sussman and Sidney D. Barlow, as well as our co pending application Serial No. 458,860, filed September 28, 1954, now Patent No. 2,787,- 249, entitled Pressurizing Means for Ink Devices, the present invention relating to improved details of construction over the structure disclosed therein.

Marking devices of the above type differ from conventional ball point pens largely in the use of heavier and more viscous inks or marking fluids, and mechanical provisions for accommodating such heavier inks. IWhil-e the actual ball point construction may resemble that of a ball point pen with minor modifications, the principal problem involved in the manufacture of such devices has centered about the incorporation of a pressurizing device which is easily operated by the user, and which while effective is relatively low in cost. While earlier constructions disclosed in the above patent and co-pending application have been efiicient in operation, the cost of fabricating such constructions has steadily risen since the invention thereof, to the point where relatively popularly priced devices can no longer be manufactured to include these constructions.

It is therefore among the principal objects of the present invention to provide an improved pressurizing structure of the class described in which the cost of fabrication has been materially reduced as compared with prior art constructions, with no decrease in efliciency or operation or potential durability.

Another object of the invention lies in the provision of an improved pressurized stopper means for use in conjunction with ball point marking devices Which may be manufactured with a complete absence of metallic parts, permitting resort to advanced molding techniques, and with a natural resistance to the deleterious effects of certain of the components of marking fluids.

Still another object of the invention lies in the provision of an improved pressurized stopper which may be readily removed or disengaged from the marking tube to permit refilling of the same with marking fluid without resort to special tools or above ordinary skill.

:Still another object of the invention lies in the formation of certain resilient moving parts in such manner that no springs are required to open or close the valves admitting additional pressure to the ink retaining chamber, thereby eliminating a potential source of rust or loss of elastic modulus.

A feature of the invention lies in the fact that several of the novel components of the inventive structure may be incorporated into a wide variety of pressurized devices, as will more fully appear hereinafter.

These objects and features, as well as other incidental ends and advantages, will become more clearly apparent during the course of the following disclosure and be pointed out in the appended claim.

On the drawing, to which reference will be made in the specification, similar reference characters have been 3,115,868 Patented Dec. 31, 1963 employed to designate corresponding parts throughout the several views.

FIGURE 1 is a fragmentary longitudinal central sectional view, partly in elevation, showing first embodiment of the invention.

FIGURE 2 is a view corresponding to that seen on FIGURE 10, but showing an altered relative position of certain of the component parts.

FIGURE 3 is a similar view showing a further altered relative position of certain of the component parts.

FIGURE 4 is a fragmentary sectional View, partially in elevation of a second embodiment of the invention, showing certain of the component parts in a first relative position.

FIGURE 5 is a view similar [l0 that seen on FIGURE 4, but showing certain of the parts in a second alternate relative position thereof.

FIGURE 6 is a similar view showing the same parts in a. third alternate relative position.

Turning now to the first embodiment of the invention as shown in FIGURES l and 2, this construction is particularly adapted for marking devices of a refillable type in which the open end of the barrel leading to the marking fluid retainingchamber is closed by threaded means. The stopper includes a main body element 51 having a threaded portion 52 and a plunger 53a arranged for ver- \tical reciprocation within the main body element 51. The lower portion of the plunger is provided with O ring means 54a for effecting a seal, the plunger 53 being automatically returned to the position shown on FIGURE 9 by a return spring 55a. The valve element 56a is of cylindrical configuration and contacts the under surface of a supporting washer 57a upon which the lower end of the return spring rests. Ihe valve element is provided with an engaging portion 58 situated in a corresponding rabbet in the threaded portion 52. The lower dome-shaped portion '60 includes a slit 61a which operates in the manner described hereinabove.

A tapered frustoconical portion 62 is disposed on the lower part of the plunger 53a. The 0 ring 54a is disposed about the tapered portion, and is of such configuration that when in unstressed condition, the outer diameter thereof is substantially equal to the inner diameter of the sleeve 64. The inner diameter of the O ring is substantially equal to the median diameter of the conical portion 53a when in unstressed condition.

From a consideration of FIGURES 1, 2, and 3, it will be apparent that when the plunger is at its uppermost position (FIGURE 1), the O ring 54a rests upon an upper spring-engaging flange member 65, the internal diameter of which is sufficiently small to prevent the same from moving upwardly upon the conical portion 62 past the position shown on the-drawing. As the plunger 53a is depressed, the O ring 54a moves relatively upwardly upon the conical portion 62 to become wedged between the same and the sleeve 64, and remains in such condition during the remaining part of the downward stroke as indicated on FIGURE 3. Upon release of the plunger 53a, the 0 ring frees itself to return to the condition shown on FIGURE 1, so that wear and stress upon the O ring occur only during the downward stroke. Referring to the lower portions of FIGURES l and 2, the tip 66 is preferably threadedly engaged with the main body portion of the device, and includes a conical outer surface 67 having flat-sided portions 68 and 69 which are engageable with a wrench or other tool for convenient removal.

Referring to the valve element 56a, the hemispherical portion 70 is bounded by an outer surface 71 and an inner surface 72, the inner surface 72 being formed with a lesser radius than that of the outer surface 71, so that a general tapering of cross-section occurs in a direction toward the lowermost point 73 where the slit 61a is formed. This construction permits ready flexing of the valve opening, while affording the valve element sufl'icient strength to assure immediate closing upon release of the plunger.

The second embodiment diflers from the principal form thereof in the location of the spring 550 within the hollow plunger 53c which is of an internal diameter sufficiently large to permit the passage of a portion of the valve 56b. It is thus possible to achieve an unusually long stroke in the plunger element as may be seen from a comparison of FIGURES 4 and 6. In the case of the second embodiment, the entire valve construction may be pre-assembled within an air casing member 90 for assembly into a completed ink device at a later stage of manufacture.

During operation of either of the embodiments of the invention it is possible for the exposed outer portion of the slitted passages to become Wet by the marking fluid and nevertheless function efliciently. Thus the need for separate liquid seals to prevent contamination of the valve structure is unnecessary. The slitted passages are open only during the time in which air passes therethrough to the ink retaining chamber, and at such time any fluid adjacent the slit is automatically pushed away therefrom. Any small amounts of marking fluid remaining upon the slitted passages merely assist in obtaining a hermetic seal therealong.

It may thus be seen that We have invented novel and highly useful improvements in pressurized stopper construction for use in conjunction with ball point marking devices, in which all of the requirements of an eflicient valve have been met and at very low cost of manufacture. Certain of the embodiments are particularly adapted for disposable type marking devices which are discarded after exhausting an initial supply of marking fluid, while other embodiments are equally well adapted for use in conjunction with marking devices of a refillable type. All of the embodiments are readily operated by those possessing only ordinary skill, and the durability of the same are at least equal to more expensive prior 'art constructions.

We wish it to be understood that We do not consider the invention limited to the precise details of structure shown and set forth in this specification, for obvious modifications will occur to those skilled in the art to which the present invention pertains.

We claim:

In a marking device including a tube, a marking tip on one end of said tube, and pressurizing means on the other end of said tube, the improvement comprising: said tube having a cylindrical bore, a plunger slidably disposed within said bore, and having an inwardly tapered portion on the inner end thereof, an 0 ring surrounding and slidably contacting said tapered portion, and having an unstressed outer diameter substantially equal to the diameter of said cylindrical bore, and an inner diameter slightly less than the greatest diameter of said tapered portion, and means adjacent the wider and narrower ends of said tapered portion for maintaining said O ring upon said tapered portion in slidable disposition, whereby movement of said plunger with respect to said bore in a direction corresponding to the direction of taper of said tapered portion may serve to wedge said O ring between said tapered portion and the surface of said bore to effect a hermetic seal therebetween, and movement in an opposite direction may serve to at least partially disengage said tapered portion from contact with said O ring.

References Cited in the file of this patent UNITED STATES PATENTS 2,001,842 Heiss et al. May 21, 1935 2,333,451 Sussrnan 'et al. Nov. 2, 1943 2,489,976 Perwas Nov. 29, 1949 2,500,998 Morris May 21, 1950 2,560,811 Morris July 17, 1951 2,613,671 Bonin Oct. 4, 1952 2,787,249 Barlow et al. Apr. 2, 1957 FOREIGN PATENTS 523,237 Canada Mar. 27, 1956 

